Rotary motor



Jan. 11, 1955 E. G. BARRETT ROTARY MOTOR 2 Shee'ts-Sheet 1 Filed April30, 1954 INVENTOR.

m0 QQ wk Jan. 11, 1955 BARRETT 2,699,151

ROTARY MOTOR Filed April 30, 1954 2 Sheets-Sheet 2 United States PatentROTARY MOTOR Elmer G. Barrett, Pampa, Tex.

Application April 30, 1954, Serial No. 426,891

Claims. (Cl. 12193) This invention relates to rotary motors of themultiple expansion type and in particular to an improvement in thepiston vanes thereof.

In rotary motors wherein a housing has a chamber formed by an outerflange portion having a radially inward facing wall and a hub portionhaving a radially outwardly facing wall in concentric relation to theflange wall and a rotating rim means carrying piston vanes pivotallymounted thereon and disposed in non-concentric relation to said wallsforming two crescent shaped working and expansion chambers with thewalls so that the rotation of the rim means causes the wall portions ofthe housing to act as cam surfaces to actuate the piston vanes betweenthe working and expansion chambers of the outer wall and rim means andthe working and expansion chamber of the inner wall and rim meanscreates considerable friction between the housing and hub wall surfacesand the piston vanes along the sealing line of contact therebetween.

Further, there is much difliculty in mounting these piston vanes on therim means in order to have a positive seal between the first working andexpansion chamber which is disposed radially outwardly of the innerhousing wall and radially inwardly from the rim surface and the secondworking and expansion chamber which is disposed radially outwardly fromthe rim flanges and radially inwardly from the outer housing wall.

It is, therefore, a primary object of this invention to provide animproved and more efficient piston vane for rotary motors of the typedescribed above which provides a decreased friction along the sealcontact between the vane and chamber walls which form the work expansionchamber of the motor.

It is a further object of this invention to provide a more efficientseal between the work expansion chambers of a rotary motor of the typedescribed above wherein there is disposed a vane which is pivotallysecured to a rotating rim.

Other objects and advantages of the invention will become apparent inthe course of the following detailed description, taken in connectionwith the accompanying drawings wherein:

Fig. 1 is an axial section of a rotary motor including my novel pistonvane in operative relation therewith;

Fig. 2 is a radial view of Fig. l with part of the housing removed andshowing various operative positions of the piston vane in dash-dotlines;

Fig. 3 is an isometric View of the rotating rim means and a singlepiston vane;

Figs. 4 and 5 are isometric views of the rim means and single pistonvane, similar to Fig. 3, but with a securing arm of the vane removed andwith the vane in various operative positions;

Fig. 6 is a vertical section through the center of a piston vane alongthe line 6-6 of Fig. 7; and

Fig. 7 is a plane view of Fig. 6 looking from 'the arrow 7.

Referring more particularly to the drawings wherein like elements arerepresented by the same reference character there is shown in Figs. 1and 2 a rotary motor generally designated 10 comprising a housing 12having mating portions 14 provided with radially extending flangeelements 16, registration elements 18 and sealing means 20. The matingportions 14 are secured together by means of bolts 22, or the like,passing through the flanges 16. It is to be understood that the housing12 is adapted to be mounted and retained in a stationary position.

Each of the housing mating portions are of a specific sectionalconfiguration, and attention is drawn to Fig. 1, wherein the housingportions 14 form a chamber 24 by reason of reduced sections 26. Thechamber 24 is enclosed on its radial outer side by Wall surfaces 28 andon its radial inner side by wall surfaces 30.

Radially inwardly from the reduced portions 26 of the housing matingportions 14 there is provided a hub element 32 adapted to receive apower take-off shaft 34 which is radially offset from the center of thecylindrical surfaces 28, 39. It is to be noted that the cylindricalsurfaces 28, 30 are concentric to each other. A rotating rim element 36is secured to rotate with the shaft 34 by means of a key 38.

Attention is directed to Fig. 1 wherein there is positionedanti-friction means 40 providing rotational movement of the shaft 34 andrim element 36 within the hub 32 of the housing 12. As shown in Fig. 3the rotating rim element 36 is of Tshape in section and comprises a hub42, stem 44, sides 46, outer surface 48 and inner surface 50 and it isto be noted that the rotating rim element and power shaft areconcentrically mounted with relation to each other, but are bothradially offset in regard to the radially disposed cylindrical surfaces28, 30.

There is provided a plurality of piston vanes generally designated 52,see Figs. 2, 6 and 7, which are pivotally mounted for radial movement onthe sides 46 of the rotating rim element 36 adjacent the rim surface 48.

For the sake of brevity I shall limit the disclosure of my invention toa single piston vane 52, bearing in mind that each of the plurality ofthese vanes is substantially identical in structure, operation andfunction. Further, I have disclosed a plurality of two piston vanes 52,in Fig. 2, and it is to be understood that more or less than four of thevanes may be used with successful results.

Attention is now directed to Figs. 35 wherein there is shown anisometric view of the rotary rim element 36 having pivotally disposedthereon a piston vane 52. As shown in Fig. 2 my novel piston vane 52 hasthe outer leg 56 thereof in frictional contact with the wall surfaces 28and the inner leg 58 is in frictional contact with the wall surfaces 30.

I shall now describe in particularity the configuration of the pistonvane 52 and it is to be noted that the outer leg portion 56 and theinner leg portion 58 are arcs of the surface of a cylinder having thediameter of the radial distance between the outer surfaces 28 and innersurfaces 30 of the chamber 24. This cylinder 59 is shown by dotted linesin Figs. 2 and 6 and it is to be noted that the cylinder circumscribesthe main body portion 60 of the piston vane 52 and provides for thedevelopment of a cylindrical body which would have a height equal to thedistance between the portions 14 which provide for the ends the chamber24. I found by providing a cylinder as developed above between thesurfaces 28 and the surfaces 30 that there would only be a frictionalline contact bgtween the sides of the cylinder and the surfaces stated aove.

The piston vanes generally used in rotary motors, of the type describedabove, are usually provided with a rectilineal frictional surfacebetween the vane and the corresponding sides of the power chambers andit is obvious that a frictional surface of rectilineal shape createsconsiderable more friction than a vane having a line contact with thecorresponding surfaces of the power chambers. It is further obvious thata cylinder disposed in the chamber 24 would not function as a vane andaccordingly I developed from the cylinder the specific piston vane 52 ofmy invention. Each of the legs 56 and 58 are merely segments of thesurface of such a cylinder and accordingly it is necessary to join theselegs by a main body element 60 which is curved in order to provide thegreatest possible area to be exposed to the working expansion of theactuation fluid. It will be noted that the resulting sectionalconfiguration of the vane is of S-shape, as shown in Fig. 6. There isfurther provided attaching means for securing the piston vane 52 to therim element 36 which in the embodiment as disclosed comprises arms 62secured to the main body element 60 and pivotally mounted on the rimelement 36 by means of a pin 64. It is to be understood that theparticular means for pivotally securing the piston vanes 52 to the rimelement 36 may be of various types and I have shown but the preferredform in this embodiment of my invention.

It should be noted that the inner edge 68 of the arms 62 are cut on anare which has a radius equal to the radius of the rim element surface50. Also the outer edge 66 of the arms 62 are cut on an arc which has aradius equal to the radius of the cylindrical surface 28. It isnecessary to so cut the edges 66, 68 of the arms 62 in order to provideclearance for the arms when the motor is in operation.

In order to provide a positive seal between the first power expansionchamber 70 and the second power expansion chamber 72 which are providedin the chamber 24 by the disposition of the rim element 36 therein, Iprovide seals 74 adjacent the edges of the outer leg 56, inner leg 58,main body portion 60 and arms 62. Further, in order to provide a smoothside 46 on the rim element 36 there are provided recesses 7 allowing thearms 62 to be positioned flush with the side surface 46 of the ring 36.There is further provided a seal element 78 in the mating portions 14 ofthe housing 12. The seals 78 are placed in a groove 80 provided in theportions 14 adjacent and in alignment with the sides 46 of the rimelement 36, not Fig. 1, and the seals 78 are urged in an axial directiontowards the sides 46 of the rim element 36 by means of leaf spring 82.

There is further provided in the rim element 36 an arcuate slot 84 foreach piston vane 52 which provides for allowing the piston vane mainbody portion 60 to be received therein when the piston vane 52 ispositioned at the farthest point on its radial inward path, note thelower vane of Fig. 2.

In order to provide clearance for the outer leg portion 56 between theouter rim surface 48 and surfaces 28 there is provided a recess 86 inthe outer surface 48. Similarly there is provided on the inner surface50 of the rotating rim element 36 a recess 88, see Figs. 4, 5, whichreceives the inner leg 58 of the piston vane 52 when the vane is in itsradially outer position as shown on the top side of Fig. 2. It is to benoted that the inner leg element 58 has provided therein a slot 90 forclearance in the inner leg element to receive the stern portion 44 ofthe rim element 36 when the piston vane pivots between its radial outerposition and its radial inner position in regard to its disposition onthe rim element.

It is to be noted that there are provided in the housing of the rotarymotor, as shown in Fig. 1 intake and exhaust ports 92 which areconnected to a source of actuating fluid, not shown. Fluid underpressure enters the first power chamber 78 through a port 92 and entersboth sides of the chamber 70 by reason of ports 91 through stem 44 andmakes one complete revolution and exhausts from chamber 70 through theother port 92 in the housing mating portion 14. The ports 92 act asintake or exhaust ports depending upon the desired rotation of themotor. The ports 92 are connected by means of a conduit 94 to an intakeport 96 in the housing portion 14 and enters the second power chamber72. The actuating fluid is allowed to have double expansion, first uponentering the chamber 70 which is of smaller area than the chamber 72,and second when the fluid enters the larger chamber 72 from chamber 70.After entering the second chamber 72 the fluid makes one completerevolution through the chamber and is exhausted to atmosphere or acondensing chamber, not shown, through exhaust port 98 in the housingportion 14.

At this time I would like to explain the operation of my novel pistonvane 52 when in use with a rotary motor of the type described above.Attention is directed to Fig. 2 wherein there are shown two piston vanes52, in solid lines, and the same vanes are shown in various operativepositions in dotted lines. It is to be understood that the actuatingfluid is admitted into chambers 70 and 72, as explained above.

Since the piston vanes 52 are carried by the rim element 36 actuation bythe power fluid against the vanes 52 cause the rim element 36 and vanes52 to rotate and the pivotal action of the vanes 52 about the pins 64causes the vanes to be properly positioned in both chambers 70, 72, bymeans of the cam action of the surfaces 28, so that the vanes willreceive the force exerted by the pressure of the expanding fluid in therespective chambers 70, 72. It is to be noted that the contacts betweenthe surface 28 and leg 56 and surface 30 and leg 58 lie on the radius ofthe concentric cylindrical surfaces 28, 30.

Further, it is to be noted that these contacts are line contacts byreason of the arcuate shape of the legs 56, 58. Also, due to the factthat the vanes 52 and rim element 36 are rotating and the surfaces 28,30 are actuating the vanes 52 into proper position the leg elements 56,58, in efiect, rock along their respective chamber surfaces 28, 30. Thisrocking effect can be noted by the comparison of the two vanes 52, asshown in Fig. 2. This rocking line contact between the vane legs 56, 58and surfaces 28, 30 respectively, decreases to a minimum the frictioncreated between the legs and chamber surfaces. This decrease of frictionprovides a more effective and ease in operation of the rotary motor.

While I have shown and described my invention as embodied in an improvedtype of rotary motor with some degree of particularity, it will berealized that the modifications and changes may be resorted to underspecial conditions. I, therefore, do not wish to be limited andrestricted to the exact details shown and described but reserve theright to make such changes and modifications as may fairly fall withinthe scope of the subject matter now being claimed.

Having thus described my invention, what I claim is:

1. In a rotary motor, a housing having concentrically disposed inner andouter wall surfaces defining therebetween an annular chamber, aplurality of power cylinders in said chamber defined by said wallsurfaces, a rim element and a piston vane, said rim element beingdisposed intermediate said wall surfaces in non-concentric relationthereto, said piston vane extending between said wall surfaces insealing arrangement with said rim element providing a seal between saidcylinders, anti-friction means providing relative rotating motionbetween said housing and said rim element, said piston vane comprising abody portion having spaced arcuate shaped wall surface engaging portionswith the arc thereof being segments of the surface of a cylinder whichcircumscribes said body portion, and means carrying said piston vane onsaid rim element with said surface engaging portions making sealing linecontact with each of said wall surfaces of said power cylinders andproviding relative radial movement between said spaced line contactswhereby effective sealing line contact is maintained between the pistonvane and the wall surfaces of said power cylinders.

2. The structure defined in claim 1, wherein said body portion of thepiston vane is arcuate and said spaced arcuate shaped wall surfaceengaging portions comprise leg elements rigid with and extending inopposite directions from said arcuate body portion.

3. A rotary motor comprising a housing having concentrically disposedinner and outer wall surfaces defining therebetween an annular chamber,a plurality of power cylinders in said chamber defined by said wallsurfaces, an annular rotor, and a piston vane element, said rotor beingdisposed in said chamber eccentrieally and intermediate of said wallsurfaces, said piston vane element extending between said wall surfacesin sealing arrangement with said rotor providing a seal between saidcylinders, said piston vane comprising a body portion having spacedarcuate shaped leg elements depending therefrom, means carrying saidpiston vane on said rotor with said leg elements making a line contactwith each of said concentric wall surfaces of said power cylindersproviding an effective sealed line contact between the piston legelements and the concentric wall surfaces, said arcuate shaped legelements of the piston vane being a portion of the surface of a cylinderhaving a diameter equal to the radial spacing of said concentric Wallsurfaces, and said means further providing relative radial movement ofsaid vane element on said rotor between said spaced line contactswhereby said effective sealing line contact is maintained between thepiston vane and the wall surfaces of said power cylinders.

4. A rotary motor comprising a housing having axially spaced side wallsand concentrically disposed inner and outer wall surfaces definingtherebetween an annular chamber, a plurality of power cylinders in saidchamber defined by said axially spaced walls, concentrically disposedwall surfaces, an annular disk type rotor and a piston vane, a driveshaft journaled in said side walls and extending radially through saidannular chamber, said annular disk type rotor being secured to saiddrive shaft between said side walls, a rim portion integral with saiddisk type rotor and disposed intermediate said wall surfaces innon-concentric relation thereto, said piston vane comprising a bodyportion having spaced arcuate shaped leg elements depending therefrom,means pivotally carrying said piston vane on said rim element with saidleg elements making a line contact with each of said concentric wallsurfaces of said power cylinders providing an effective sealed linecontact between the piston leg elements and the concentric wallsurfaces, said arcuate shaped leg elements of the piston vane being aportion of the surface of a cylinder having a diameter equal to theradial spacing of said concentric wall surfaces, said means comprisingarms secured at one end thereof to the main body portion of said vaneand pivotally mounted on the rim element and a radially extendingarcuate shaped slot in said rim element providing clearance for saidmain body portion during relative movement of said piston vane on saidrotor between said spaced line contacts causing a constant effectivesealing line contact between the piston vane and the concentric Wallsurface of the power cylinder during the transmission of rotary power tosaid drive shaft for said rotor.

5. The structure defined in claim 4 wherein said body portion of thepiston vane is arcuate and said spaced arcuate shaped wall surfaceengaging portions comprise leg elements rigid with and extending inopposite direction from said arcuate body portion.

Palle July 15, 1902 Speese Apr. 18, 1916

